摘要
近年来,金属有机骨架(MOFs)逐渐用于析氧反应(OER)领域。在以往研究中,MOFs通常作为前驱体在高温下热解制备金属氧化物/多孔碳复合材料以提高OER性能。虽然金属氧化物/多孔碳复合材料显示出较高的催化活性,但是它们需要复杂的制备工艺和高温条件。因此,寻找一种不经过热解处理可以直接用作OER的高效能MOFs催化剂是有意义的。结果表明,以Co-ZIF-67/NF、Ni-MOF-74/NF和Fe-MIL-101/NF为OER的催化剂时,在1 mol/L KOH溶液中电流密度达到10 mA/cm^(2)所需过电位分别为377、383和272 mV。Fe-MIL-101/NF的电荷转移电阻(R_(ct))为1.53Ω,小于Co-ZIF-67/NF(32.40Ω)和Ni-MOF-74/NF(43.78Ω)。因此,随着催化剂的R_(ct)逐渐增大,OER过程中的电荷传递能力降低,即快速的电荷转移速率是Fe-MIL-101/NF具有优异OER活性的主要原因。另外,不经热解处理的Fe-MIL-101/NF(272 mV)的OER活性明显高于商业RuO2/NF(302 mV),说明具有快速电荷转移速率的MOFs可以不经煅烧作为OER的高效催化剂。
In recent years,metal-organic frameworks(MOFs)have gradually been used in the field of oxygen evolution reaction(OER).In order to improve OER performance,MOFs are usually used as precursors to prepare metal oxide/porous carbon composites by pyrolysis at high temperatures in previous studies.Although metal oxide/porous carbon composites show high catalytic activity,they require complicated preparation processes and high temperature.Therefore,it is very significant to find a highly efficient MOFs,which can be directly used as OER without pyrolysis treatment.The results show that when Co-ZIF-67/NF,Ni-MOF-74/NF and Fe-MIL-101/NF are used as OER catalysts in 1 mol/L KOH solution,377,383 and 272 mV overpotentials are required to make the current density achieve 10 mA/cm^(2).The charge transfer resistance(R_(ct))of Fe-MIL-101/NF is 1.53Ω,which is smaller than that of Co-ZIF-67/NF(32.40Ω)and Ni-MOF-74/NF(43.78Ω).Therefore,the higher of the R_(ct) of the catalyst,the smaller of the charge transfer capacity in the OER process.Thus,the fast charge transfer rate is the main reason for the excellent OER activity of Fe-MIL-101/NF.In addition,the OER activity of Fe-MIL-101/NF(272 mV)without pyrolysis treatment is much higher than that of commercial RuO2/NF(302 mV),indicating that MOFs with fast charge transfer rate can be used as an efficient catalyst for OER without calcination.
作者
彭学刚
李晓东
崔丽萍
高志华
黄伟
左志军
PENG Xue-gang;LI Xiao-dong;CUI Li-ping;GAO Zhi-hua;HUANG Wei;ZUO Zhi-jun(State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China;College of Chemistry and Chemical Engineering,Jinzhong University,Jinzhong 030619,China;College of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2021年第9期1354-1361,共8页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金面上项目(21776197,22078214,21776195)
山西省重点研发计划(国际科技合作,201903D421074)
山西省高等学校科技成果转化培育项目(2020CG012)
山西省科技重大专项(20191102003)项目资助。
